Prefabricated assembly type stair support gasket sealing device

The utility model discloses a gasket sealing device at the position of a prefabricated assembly type stair support, which comprises a cast-in-place stair plate joint surface and a prefabricated stair, a stair plate matching groove is arranged on the cast-in-place stair plate joint surface, a fixed hinge end node is arranged on the prefabricated stair, a connecting rib piece is connected onto the stair plate matching groove, and a gasket is arranged on the connecting rib piece. A pin key reserved hole is formed in the surface of the fixed hinge end joint in a penetrating mode, a leveling layer contact face is arranged between the ladder plate matching groove and the fixed hinge end joint, and a sealing rubber gasket is arranged at the bottom end of the pin key reserved hole. The fixing hinge end node has the beneficial effects that concrete in the pin key reserved hole and the connecting rib piece can be formed into a whole, connection and fixation of the fixing hinge end node and the stair plate matching groo